The miniaturization and integration of spectrographic equipment, using MEMS (Micro Electromechanical Systems) devices, for example, draw great attention for the potential application of spectrographic techniques to different fields of technology. Wavelength signature detection, for example, has immense potential for application in such fields as telecommunications, biological sensing, chemical sensing, and sensing of other material properties that respond through spectral variation of light. Chemical and biological sensing and diagnostics have a tremendous potential for applications in many fields including defence, medicine, space, aerospace, etc.
However, widespread application of known detection techniques has been hampered by the typically large size and high cost of equipment. According to conventional design techniques, equipment is not application-specific, and is instead adapted for many different uses. For example, different chemical or biological species have different combinations of wavelength signature or peak wavelengths for detection. Hence, using a general wavelength detection equipment for the detection of different species becomes highly demanding due to the wider range of wavelength and finer wavelength resolution required in such applications.
In a spectrometer, all signature wavelengths are generally imaged on a detector array with constant array spacing, such that a large number of detector array elements is required in order to cover a full wavelength range of interest, leading to increased equipment costs. Furthermore, in the detection of specific chemicals or biological specimens with a characteristic spectrum over a wide wavelength range, not all wavelengths, and therefore not all elements in a large detector array, are needed. This results in unused detector elements corresponding to non-excited wavelengths.
Known wavelength detection equipment is also characterized by relatively large required sample quantities, as well as long light paths between the sample and a detection unit, which affects equipment size.